/*
 * WorldEdit, a Minecraft world manipulation toolkit
 * Copyright (C) sk89q <http://www.sk89q.com>
 * Copyright (C) WorldEdit team and contributors
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package com.sk89q.worldedit.function.util;

import com.sk89q.worldedit.MaxChangedBlocksException;
import com.sk89q.worldedit.WorldEditException;
import com.sk89q.worldedit.function.RegionFunction;
import com.sk89q.worldedit.math.BlockVector3;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;

/**
 * A filter that limits the number of changes that can be made.
 */
public final class ChangeLimitingFilter implements RegionFunction {

    private final RegionFunction function;
    private final int limit;
    private int count = 0;

    /**
     * Create a new change limiting filter.
     *
     * @param limit the limit
     * @param function the function
     */
    public ChangeLimitingFilter(int limit, RegionFunction function) {
        checkNotNull(function);
        checkArgument(limit >= 0, "limit >= 0 required");
        this.limit = limit;
        this.function = function;
    }

    @Override
    public boolean apply(BlockVector3 position) throws WorldEditException {
        if (count >= limit) {
            throw new MaxChangedBlocksException(limit);
        }
        count++;
        return function.apply(position);
    }

}
